My wife and I did two dives in these shark-infested waters and encountered “raggies” by the dozen. Most were about 1.5 to two meters (4.5 to 6.5 feet) long I reckon but some were larger (the females tend to be bigger than the males).

The visibility was not great so I have no idea how many were really out there. Scores or possibly hundreds I suppose.

Divers are not supposed to go within five meters of the sharks but the sharks don’t follow the same guidelines and sometimes swim right past you, a permanent ragged-tooth “smile” etched in their faces.

Did they look sinister? Of course! But they did not strike me as aggressive in the least (though I have to confess that I would have been less comfortable around great whites).

And after about 30 minutes of constant shark sightings our group drifted over the “cathedral”, which is sort of an open cavern where dozens of raggies swim slowly in circles.

I saw it as I started my gradual ascent to the surface (I was getting low on air) and it was a thrill to realise that so many sharks were circling below me.

The folks at Aliwal Dive Center, the outfit we took the plunge with, said this year has been the best for raggie diving in at least a decade. And they see such close encounters with sharks as good for conservation as they help to dispell man-eater myths.

“Sharks have had such bad press,” said Aliwal manager Nigel Pickering.

There have been concerns in some conservation circles that divers have contributed to declines in the number of sharks coming to the area in recent years — perhaps the animals are shy of odd creatures spewing bubbles — but the numbers this season suggest the reasons behind this state of affairs are probably more complex.

Shark numbers globally are in decline in part because of the unsustainable harvesting of shark fins for soup, a coveted delicacy in Asia and elsewhere. So any sign of a recovery such as the raggie numbers this year off South Africa is good news.

Against this backdrop, it certainly seems to me that diving with raggies can do no harm. Scuba diving done properly is not an intrusive or disruptive outdoor activity.

And like many other eco-tourist pursuits it can’t hurt to make it commercially valuable to see the animals up close. This gives people a vested interest in protecting rather than eating them.